A fiber optic cable may include one or more optical fiber ribbons capable of transmitting voice, television, or computer data information. Examples of optical fiber ribbons are disclosed in U.S. Pat. Nos. 5,561,730 and 5,457,762, which are incorporated herein by reference. Optical fiber ribbons may be made by arranging a plurality of optical fibers in planar relationship, and then extruding a common matrix coating, such as a UV curable acrylate material, about the optical fibers. FIG. 1 is an enlarged cross sectional view of a conventional optical fiber ribbon C with twelve optical fibers F, each fiber having a respective buffer layer B. Conventional optical fiber ribbons C may or may not have spaces between adjacent buffer layers B. Often the connectorization of optical fibers F requires ribbon C to be separated into optical fiber subsets. The respective ends of the subsets are then stripped of the common matrix coating, and buffer layers B are removed thereby exposing the optical fibers. The optical fibers are then ready for connectorization.
FIGS. 2 and 3 illustrate a known ribbon separation tool 1 used for separating a single optical fiber ribbon into optical fiber subsets. Ribbon separation tool 1 comprises a housing 2 mounting a reciprocal member 3. Reciprocal member 3 is moveable along a line of action L when a pressing force is applied to a button 5. Ribbon receiving slots 4 are arranged to receive a single optical fiber ribbon C. Reciprocal member 3 includes blades 6 fastened thereto, which blades are designed to shear optical fiber ribbon C in a shearing stroke of reciprocal member 3. Cooperating with and hingedly mounted to the housing base is a pair of cover members 9 which are separated by a slit S. Each cover member 9 includes respective shearing blades 7 that cooperate with blades 6 to effect shearing of optical fiber ribbon C. Maintaining pressure on button 5, and at the same time pulling sheared optical fiber ribbon C to its end, results in a lengthwise separation of optical fiber ribbon C into two optical fiber subsets. Each of the two subsets has a number of optical fibers therein, for example, the two subsets include six fibers each.
Known ribbon separation tool 1 has several disadvantages. First, it is limited to separating but a single optical fiber ribbon C per shearing stroke, such that plural ribbons may only be separated in a time-consuming series of shearing strokes. In addition, only two subsets of optical fibers can be made by blades 6,7 per shearing stroke; if numerically different subsets of optical fibers are needed, blades 6,7 must be replaced with different sized blades which will result in numerically different subsets of optical fibers. Replacing blades 6,7 is a time consuming procedure; moreover, an expensive inventory of different sized blades 6,7 must be maintained. In a further disadvantage, as best seen in FIG. 3, the only way to adjust the length of the shearing stroke of reciprocal member 3 is by adjusting a screw 8 with a special tool, e.g. an Allen wrench. This is disadvantageous because making such an adjustment is a time-consuming procedure, and because a craftsman must keep such a special tool on hand to make the adjustments as needed. Furthermore, gap G, which exists between reciprocal member 3 and housing 2 and which allows space for the shearing stroke of reciprocal member 3, is exposed to the outside environment of ribbon separation tool 1. Such exposure is a problem because foreign matter may enter gap G and decrease or altogether block movement of reciprocal member 3 along its line of action L, thereby resulting in an incomplete or a non-shearing of optical fiber ribbon C. Additionally, as cover members 9 and blades 7 are separated at line S, the covers 9 may move independently of each other; consequently, blades 7 may be misaligned during the shearing stroke, possibly causing damage to optical fiber ribbon C and optical fibers F. Moreover, shearing blades 6,7 are not multi-edged: when either of the blades becomes dulled from use, it must be removed, and either sharpened and re-used or altogether replaced with a fresh blade.